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Can I change the delay between each external trigger on my PCI-6602?

I have an external source (30Hz) that does not change. I want to trigger a PCI-6602 board with this external trigger and create a pulse with a delay from the trigger. The delay number will change on each trigger. The delay is derived from a theoretical range of a missile launch, so it is not a linear change.
I am using Labview 6 and Windows NT 4.
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I think the answer is probably. However, you can't do it with hardware timing from the acq. board. You'll need to depend on software reprogramming, which means that at best, you may be able to change the delay time before *most* of the input triggers.

Method:
1. Configure counter for "Retriggerable Pulse Generation", but you probably already know this.
2. Detect when first pulse has been generated after its delay has expired. Poll "Counter Get Attribute.vi" for "output state" (or maybe "TC reached" -- I'm not at my acq. PC to test it right now) until you detect the transition.
3. Call "Counter Set Attribute.vi" with "pulse spec 1" as the Attribute ID, and your new delay value (in timebase cycles) as the Attribute Value Number.
4. Call "Counter Control
.vi" with "switch cycle" as the action.
5. Hopefully, you got all that done before the next input trigger! If not, I *think* the pulse will still be generated, but based on the prior delay value.

6. My multi-year running gripe with NI on counter/timer functionality: When oh when will NI-DAQ support the ability to generate buffered pulsetrains where the delay and/or pulsewidth can change for every cycle?
The output equivalent of buffered semi-period input measurements would be *very* helpful. Then I could capture a pulse timing pattern observed on a full-up prototype unit and *re-create it* as a stimulus in a controlled lab environment. The same sort of thing we've been able to do with analog i/o for years. It's a very real and obvious hole in functionality for the 6602, a device that is otherwise quite impressive.
End of gripe.
ALERT! LabVIEW's subscription-only policy came to an end (finally!). Unfortunately, pricing favors the captured and committed over new adopters -- so tread carefully.
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Brad

I'm not exactly sure what you are trying to do. However, a solution may be to wire your external 30 Hz source to the gate of a counter and use that as the timebase for a pulse generation application.

Let me know if this will not work. Also, give me some more info to your application.

Brian
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